"We had to try something," the City boss told Sky Sports after the game.
"We were getting a foothold in the game without threatening enough.
"In Ali (Benarbia) we've got invention, Shaun got his 100th goal against United and has now scored again today. Having been here as a kid he'll have enjoyed that.
"We're still building and trying to be where they (United) have been for a long time. You've got to come here with no fear, but I'm delighted for our fans.
"We've proved we're as good as them today - and that's pleased me.
"We're unbeaten against them this season. I don't know how many clubs will be able to say that at the end of the season."
Match Report